Coagulation-sedimentation-rapid

Fig. 10. Plots of particle size distribution in effluent of one-layer rapid sand filtration after coagulation-sedimentation ...

This division is very convenient from the point of view of particle characterization and measurement. Thus, in the range of Aitken particles diffusion effects are significant and particle coagulation is rapid. However, in case of giant particles these phenomena can be neglected and the behaviour of aerosol particles is mostly determined by their sedimentation due to gravitation. The large particles constitute... 

Because of the rapid modifications of the physicochemical and microbiological characteristics of natural water samples, initiated by changes in temperature, pH, depth, dissolved O2 or CO2, light, and convection, aquatic samples should be processed for electron microscopy without any delay to avoid dissolutions, precipitations, coagulations, sedimentations, microbial growth, or shifts in chemical... 

Logan BE, Passow U, Alldredge AL, Grossard HP, Simon M (1995) Rapid formation and sedimentation of large aggregates is predictable from coagulation rates (half-lives) of transparent exopolymer particles (TEP). Deep-Sea Res 42 203-214... 

The optimal concentrations were determined at which iron and silica sediments separate rapidly from a mixed sol as it coagulates, forming banded jaspilite-like layers. In these experiments, differential deposition of iron... 

Aerosol particles used for inhalation deposit within the lower respiratory tract mainly by inertial impaction, sedimentation, and diffusion. Loose fractal aerosols were found to settle slower and therefore had more time to increase gravitational coagulation with other floes leading to much more rapid particle growth. This will increase the chance of the aerosol floes settling on the airway walls before reaching the end of the airways. 

The coagulation process was investigated by the jar-test method with the following parameters rapid mix (G = 200 s ) for 2 minutes, flociUation (G = 20 s ) for 20 minutes, and sedimentation for 30 minutes. After the sedimentation process had been completed, determinations were carried... 

The less rapidly coagulating Al3+ floe system (a = 0.35) is separated in flotation nearly as effectively as the better coagulating Fe3+ floe system (a = 0.59). In fact, this system appears more suitable for flotation than the quite effective polymer floe formation system (a= 0.47), which has been removed to a more satisfying degree in sedimentation. The Fe3+ plus polymer floe system (a = 0.84) shows the best removal efficiency, as it does also in sedimentation units. 

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